Moistening device for duplicating machines



Dec. 19, 1950 A. v. DlTTY MOISTENING DEVICE FOR DUPLICATINGMACHINES Filed May 14, 1945 2 Sheets-Sheet 1 IN VEN TOR.

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A. V. DlTTY MOISTENING DEVICE FOR DUPLICATING MACHINES Dec. 19, 1950 Filed May 14, 1945 2 Sheets-Sheet 2 w m m m y W 0 V. W m

Patented Dec. 19, 1950 MOISTENING DEVICE FOR DU PLICATIN G .MACHINE S.

AIIan.V.'Ditty;, Grosse Pointe, Mich., assi'gnor to Arthur J. Bradford ApplicationMay 14, 1945, Serial-1N0. 593,647

This. invention. relates to a duplicating machine of the type in which a. plurality of copy sheets may bemade from a master sheet.

The particular type of duplicating machine in questionhasa cylindrical or drum platen around which a master sheet with, reversed, raised, solublew characters is wrapped and fastened. opy sheets are then passed, to the drum while it, is rotating andpressed against the. raised characters oi. the mastersheet on thedrumwithasmali amount of-pressure. Prior to, meeting the, master these copy sheets are. moistened with a volatile, dissolving, liquid such as. alcohol, which. will :temovezfrom the master sheets a very small quantity of the raised characters-thereon, which debe evenly distributed without danger or large quantities being; deposited at the. initial contact by the sheet. In previous constructions, such as that shown .inthe'patent to Morris No. 2,229,583, absorbent wicks have been used to apply the liquid to the copysheet. The present invention is considered an improvement over the wick type of applicator in that it affords control. and consistency in the distribution of the moistening material and is more economicar over long periods 'of use.

vAnother advantage of. the present construction iie'siin. the; design which permits. the entire sheet to be moistened including the: top margin. In previous designs it has been necessary to passthe top-marginto the frictional drivelconnection, thus removing it-from the wetting zone.

Other objects and features of the invention relating to a novel method of mounting the operating rollers and other details will be found in the following description and claims:

In the drawings:

Fig. 1 is a sectional view through a portion of the duplicator machine showing the platen drum and the rollers aligned therewith.

Fig. 2 is a plan view of the platen drum and a portion of the machine.

Fig. 3 is a sectional view on line 3-3 of Fig. 1.

Fig. 4 is a sectional view of the porous roller on line 4-4 of Fig. 3.

Fig. 5 is a sectional view on the line 55 of Fig. 1.

With reference to the drawings, a platen drum I is supported in a housing H by a. journal I2 at one end, and a pinion passing to a crank l3 at the other. A table l4 on the housing ll pro- 3'Claims. (cm-49 videssupport for the copy paper l which is fed to the platen roller. A feed roller and a feed roller 2I are mounted in parallel relation on a rocker bar 22 which is pivoted on a member 23.

A. pin 26 mounts the member 23 which extends at 25 to a cross piece 26. A threaded pin 2.! is tapped into cross piece 26. and extends upwardly to a transverse member 28 between sides ll.. As shown in Fig. 5 a yoke 29 on pint? bears against member 23. A finger wheel 27a serves to facilitate turning ofpin 21 to exertdownward pressure on extension 25-. this pin 21 permits equalization of pressures between the rollers 26 and 2| and the porous rolier'a-nd platen with a single adjustment.

Roller 2-8 bears against the drum platen l9. Roller 2i bears with. an equal amount of pressure against a roller til: which is the moisteningroller. A crossed belt 3 ii ccnneetspulley wheels on rollers 26 and 3E, respectively. As roller 23 is rotated by the contact; with-drhzen. drum Iii, the roller 30. will likewise be: rotated. A felt wiper 33 is contained in a'long-itudinal recess or retainer 3Q on'member Any excess accumulation of liquid. on rolls 30 and 2 i will be collected by this wiper. When paper is fed to the rolls 2: and 33 .it will pass between rolls lit and 29 where it contacts the master sheet to receive copy and thenv passes through-the machine.

Detailsof the moistening roller designated '30 are shownin- Fig. 3. The contacting portion 40 of theroller is tube-likein form and has a porous structure, the pores being of such minute nature that, when moistening fluid passes through or exudes from them, the outer surface of the roller appearsto sweat. Examples of a suitable material are:

(A) Diatomaceous earth; (B) Alfrax (made by the Carborundum Comeither of which materials is used as a filtering medium in laboratory work for isolating virus or other minute particles from a liquid. Alfrax is available in varying degrees of porosity depending on the purpose for which it is intended.

One end of the tube id is supported by a collar 4| rotatably mounted in a flanged piece 42 at one side of the housing H. The other end of the roller assembly is formed by a pulley 43 having a pinion 44 bearing in a bushing 45. The pulley 43 seals one end of the tube and a closure type wiping seal 46 surrounding an inlet tube 4'! seals on the other end of the porous tube. A circular coil spring 48 holds a sealing member 46 close against the tube 4? but permits rotation about such tube.

Inlet tube 41 is supportedat each end by member 42 and pulley 43, respectively and is concentric with a tube 419 of smaller diameter. A pump 50 in a tank 5| has an operating plunger 52 suitably reciprocated by rotation Of, the platen to force liquid through a supply tube 53 to a passage 54 in member 42 which leads to, the inner tube 49. Holes 55 are provided along tube 49 at a point slightly above the axis thereof so that liquid furnished to the tube will flow along the entire tube and spill over the holes 55 into the tube 4! which is provided with holes 55 along its length through which the liquid will be evenly distributed throughout the length of the porous tube 40. This tube-within-a-tube construction insures an even distribution of liquid through the porous tube since liquid will flow from the inner tube to fill the outer tube evenly in its entire length. Flow from each of the holes 55 will be substantially equal.

As roll 46 is rotated in the operation of the machine, the liquid thus furnished to the inner walls will be distributed around the entire tube and the porosity of the tube will absorb the liquid which will pass gradually through to the outer surface where it will be distributed to the sheets l5 as they pass to the master roll.

Liquid will exude from the pores of the roller by capillary action but this action may b hastened by building up a pressure within the porous roll by means of the pump 58.

It will be understood that roll 2 I could be driven by roll 26 and roll 30 driven by friction without departing from the invention. Similarly the felt wick could wipe directly against roller 30 rather than against roll 2| as now shown.

What I claim is:

1. In a duplicating machine for making a plurality of copies from a soluble master sheet fastened to a drum platen, a means for moistening the copy sheets with a dissolving liquid prior to contact with the master sheet comprising a porous tube positioned to rotate in parallel relation with said drum in the path of the copy sheets being fed thereto, means to feed moistening liquid to the inside of said tube, comprising stationary concentric tubes axially positioned within said porous tube extending the length thereof and provided with holes spaced upward from the lower surface, means sealing the ends of said porous tube around said concentric tubes to permit relative rotative movement, and means to feed liquid to the inner of said concentric tubes under pressure.

2. In a duplicating machine for making a plurality of copies from a soluble master sheet fastened to a drum platen, a means for moistening the copy sheets with a dissolving liquid prior to the contact with the master sheet comprising a porous tube positioned to rotate in parallel relation with said drum in the path of the copy sheets being fed thereto, and means to feed moistening liquid to the inside of said tube comprising a, pair of concentric tubes positioned axially within said porous tube independently of said concentric tubes, a rotary seal mounted at one end of said porous tube outside said concentric tube to confine liquid at one end of the assembly, and a cap sealing the ends of the concentric tubes at the other end of the porous tube servin as a mount for the concentric tubes at the closed end, said inner concentric tube being apertured at points at the axis or above and being adapted to receive moistening liquid, and said outer concentric tube being apertured to said liquid tothe inside of the porous tube as it rotates.

3. In a duplicating machine for making a plurality of copies from a soluble master sheet fastened to a drum platen, a means for moistening the copy sheets with a dissolving liquid prior to contact with the master sheet comprising a porous tube positioned to rotate in parallel relation with said drum in the path of the copy sheets being fed thereto, means to feed moistening liquid to the inside of said porous tube comprising concentric tubes within said porous tube extending the length thereof axially of the porous tube, sealing meansat the ends of the concentric tubes to form an annular chamber within the porous tube and being arranged to permit relative rotatable movement between the concentric tubes and the porous tubes, and means to feed liquid to the inner of the concentric tubes, the concentric tubes being apertured to feed such liquid to the annular chamber throughout the length of the porous tube.

ALLAN V. DITTY.

REFERENCES CITED The following references are of record in the file of this patent;

UNITED STATES PATENTS Number Name Date 1,645,930 Ritzerfeld Oct. 18, 1927 2,161,554 Benello June 6, 1939 2,165,972 Kokay July 11, 1939 2,189,765 Takats Feb. 13, 1940 2,267,982 Kokay Dec. 30, 1941 2,349,634 Neal May 23, 1944 

